Poise for weigh beams



Patented Oct 14, 1924.

UNITED STATES PATENT OFFICE.

MORTON H. STARR, OF ST. JOHNSBURY, VERMONT7 ASSIGNOR TO E AND T. FAIR- BANKS AND COMPANY, 0F ST. JOI-INSBURY,e VERMONT, A OORQOBATION' 0F VER- MONT.

POISE FOR WEIGH BEAMS.

Application filed May 8,

To all whom 'it may concern.'

Be it known that I, MoR'roN H. STARR, a citizen of the United States, residing at St. Johnsbury, in the county of Caledonia and State of Vermont, have invented certain new and useful Improvements in Poise for Weigh Beams, of which the 'following is a full, clear, and exact description, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to improvements in poise construction for weigh-beams for use with scales, and particularly in some of its details, for use with high capacity scales such as are adapted for installation on railway tracks.

The invention has for its general object. improvements in poise construction for weigh-beams or the like, providing a poise which is relatively simple, reliable and exact in function under varying conditions of service, and susceptible of operation with a minimum of effort. l

Another object is to provide an improved locking means operating mechanism therefor and for other operative elements of poises of theclass mentioned, automaticall.;r securing the poise in different operative positions whereby operation is simplified and facilitated.

Still another object is to provide an improved means for locking a poise of the class mentioned to the supporting weighbeam, so arranged as to remain automaticall);7 in unlocked position, simplifying` the operation of adjusting the poise along the weighbeam and balancing the scale.

Other objects will be in part obvious from the following detailed description of an illustra ive embodiment, and will be in part pointed out in connection therewith.

The invention accordingly consists in the 'features of construction, combinations of elements and arrangement of parts which will be exemplified in the construction` hereinafter set forth, and the scope of their application will appear in the appended claims.

For a complete understanding of the na- 1922. Serial No. 559,176.

ture of the invention reference should be had to the accompanving drawings wherein disclosed the best form at present known, and to the detailed description thereof. In said drawings,

Figure 1 .is a fragmentary front elevation of a weigh-beam and poise embodying the invention;

Fig. 2 is a rear elevation, certain parts being broken away more clearly to disclose the structure, the locking mechanism being shown in unlocking position;

Fig 3 is a sectional view takenon the line 3-3 of Fig. l; looking in the direction indicated by the arrows;

Fig. 4 is a horizontal section taken approximately on the line 4-4 of Fig. 2 look ing in the direction of the arrows, and

Fig. 5 is a detail perspective view showing the operating cam and slide.

Referring to the drawing for a detailed description of the embodiment of the invention as shown, the weighsbeam l is mounted in any approved manner for connection with the weighing elements of scale, and is preferably inverted U-shape in ciosssection, as disclosed in co-pending application Serial No; 441,554 filed February 1, Y1.921.

The poise 2 is mounted on the weigh-beam by means of a carriage having rollers 3 arranged in triangular formation for a threepoint suspension, being supported on tracks 4 formed on the inner surfaces of the walls of the downwardly extending legs of the weigh-beam, providing runways so the poise may be rolled along or adjustedlongitudr nally tov obtain an approximate balance. Fine adjustment for balancing this scale beam are made by means of an adjustable auxiliary or fractional'poise 5 which may be operated by means of a rack and pinion mechanism through a hand wheel or knob (i, as fully set forth in said priorY application.

The Weigh-beam may be mounted in any approved manner but is preferably mounted as shown in 'said co-pending application No. 441,544 and is designed particularly for use in connection with high capacity scales such,

for example, as are employed in railway work and the like, but it is tobe understood that the construction is susceptible of other application.

Itis desirable to lock the poise in adjusted position after a balance has been reached while the process of recording weight by appropriate means is being performed. F or this purpose there is a locking mechanism including an` elongated locking bar 7 carried by one leg of the weigh-beam and extending along the lower edge thereof, and having a downwardly facing toothed. or serrated face 8. This locking bar is co-e.\;-

tensive with the range of travel of the poise.`

An elongated pawl 9 having a multiple toothed or serrated face 10 is mounted en the'poise with its face lyingy parallel to and in4 juxtaposition to the face 8 of the lockingV bar. This pawl is mounted on a slide 11 confined for vertical sliding movement in guide-ways 1.2 formed` in the poise. Compression: springs 13 are confined between opposite extremities of the pawl and opA posed abutments 141 on the poise, and are held inA position by retaining posts 15 removably seated in the pawl extensions and abutments. The y'terminal .portions ofsprings 13 surround these retaining posts and the springs are thus held removably in position. These springs are normally stressed to urge the paw-l into locking engagement with the locking bar to lock the pawl against longitudinal movement. The multiple toothed pawlA construction designed for prevent ing errors in adjust-nient of the poise is fully explained in said prior application.

The slide 11r has a rectangular opening 16, at theV lower side of which is mounted a roller 17 having its periphery extending slightly beyond the inner face ofthe lower wall of the opening. in operating cam 18 is disposed within said opening, being rig idly mounted on a shaft 19 rotatable in bearings in the poise and carrying anoper ating handle 2O at its outer extremity. The operating surface ofthe cam 18 is approxr mately heart-shaped, and the base 21 being disposed relatively near to the center of rotation the minor ordinate being disposed at this point and increasing therefrom toward the point 22 where the majork ordinate is located. This point forms a lobe or projectionl on the cam face which is reversely curved at opposite sides of the point or apex. of the dotted line extending through the center of the operating camshaft, as shown in Fig. 2. The cam face between the base 21 and the apex 22, and extending also somewhat beyond said apex, is' adapted to contact with the roller 17 for operation of the slide 11, and the pawl carried thereby against the force of springs 13. A pointer orindex 23 is carried by the handle 20, be-

These surfaces lie on opposite sidesV ing adapted to swing over the dial plate 24 to indicate the different positions of the cam shaft.

A coil spring 25 is supported on a post 26 secured to the poise, beingA wound around the post and having a fulcrum extension 27 lying in position to engage the vertical face of the side wall of the slide opening 16. rlhe working arm 28 of this spring is conu nected to a pin Q9 secured to the cam, an elongated loop being provided to effect this connection. ri pin 30 supported by a wall of the poise forms a lug or stop for engagement with the shoulder 31 of the cam, limiting movement of the latter in one direction, as clearly shown in Figs. 2 and 5.

The recoruing or printing mechanism shown particularly lin Fig. 3. rThis comprises a type bar 3Q carried by the poise, type 33 being mounted thereon and on the adjacent auxiliary or fractional poise 5. A printing hammer or dog 34 is slidably mounted to l1o-operate with 'the type to print weights on' a ticket which may be inserted in position through the slot 35. .The-

hammer is carried by a plunger 3G connected to the lower extremity of which is a roller 37 lying in a position to cooperate with an eccentric cam 38 mounted on the cam shaft 19. This cam is mounted on the cam shaft with the major ordinate lying at an angle to that of the heart-shaped cam 18.

The locking pawl operating mechanism of the poise is mounted in a cavity or recess formed therein and is protected by a cover plate l0 secured to the. face of the poise and also forming a finishing surface therefor.

lointers Ll1 and et@ are provided for the poise, the former being adapted to pass over a scale to indicate approximate readings, while the latter is mounted upon the fractional poise to pass over a second graduated scale :indicating corrections so the eX- act weight can be read. These movements also bring appropriate type in registryY with the hammer 234-.

ln operating the poise to secure a balance for the scale, the operating handle Q0 is turned into vertical position, as indi cated in Fig. l, the index 23 then in dicating C open l position. r. his moves the operating cam 18 into engagement with the rollerl 17 to move the slide and loching pawl into unlocking positionso the teeth thereof will clear those ofthe locl'ring bar 7, as clearly shown in F E2. the time this position of the pawl is reached the nose of the lobe E22 of the cam aasses slightly beyond the contact: point hetween the cam androller. and the lug 3l at this time contacts with the stop pin 3U. llt' will thus'be seen that the tension of` springs 13 tending to force the pawl toward its locking position acts through the roller 17 and the cam lobe to lock the parts in the position shown in Fig. 2. The poise may then be rolled freely along the Weigh-beam to reach a balancing position Without the necessity of manually holding the handle in its unlocking position. When the point Ahas been reached for an approximate balance, the handle is operated in the opposite direction to the dot and dash line position shown in Fig. 1. The index 23 then indicates locking position and the pawl is permitted to move to locking position under the influence of compression springs 13.

During the movement" of the cam from the unlocking position shown in Fig. 2 to the locking position th-e Working arm of spring 25 is moved in a clockwise direction, as viewed in said figure, placing the spring under tension to oppose movement of the cam shaft beyond the locking position. Further movement to dotted line position of this shaft and handle, in a clockwise direction as viewed in Fig. 2, to the print position places the spring 25 under tension, and when pressure on the handle 2O is released the shaft. will return automatically under this pressure to the lock position. During this movement of the cam shaft from the lock position to the print position the cani 18 will be inoperative to move the pawl 19, the latter then being in locking engagament With the locking bar 8, While cam 38 will engage the plunger 36 to move the print hannner 34 to make an impression upon the record ticket. It will be noted that the spring 25 begins to be placed under tension about the time the face of cam 18 first contacts With rolle-r 17 in its counter-clockwise movement from locking position toward unlocking position as viewed in Fig. 2. At this time the Jfulcruln arm 27 contacts with the wall of the opening 16 as described. It is further noted that the springs 25 are relatively Weak in comparison with springs 13 .so as to exert substantially no influence on the latter in their action tending to move the locking paid-toward locking position.

As many changes could be made in tht above construction and many apparently widely different embodiments of this inven tion could be made without departing tron. the scope thereof. it is intended that all mat` ler contained in the above description or shown in the accompanying drawings shall be interpreted as illustra-tive and not in a limiting sense.

lt is also to be 'understood that the langauge used in the following claims intended to cover all of the generic and specific features of the invention herein described and all statements of the scope of the invention, Which. as a matter of language, might be said to fall therebetween.

Having described my invention, what l secure by Letters' claim as new and desire to Patent, 1s:

1. In a Weighing device, in combination, a Weigh-beam, a poise supported by said Weigh -beam and movable thereon, means for locking said poise on said Weigh-beam, means for operating said locking means, weight printing mechanism, said ope-rating means when operated one way being adapted to automatically hold said locking means, in unlocking position, aid when operated another Way being` adapted to sequentially lock the poise and operate said printii'ig mechanism.

2. In a Weighing device. in combination, a Weighbeam, a poise supported by said Weighbeam and movable thereon, a locking paWl for said poise., having an elongated locking face and norn'iially biased to locking position, said pawl being moiinted so that said locking face moves parallel to itself. means for operating said locking pawl. and automatic means for holding said locking pavvl in unlocking position in opposition to said bias.

3. In a Weighing device, in combination, Weigli-beani, a poise supported by said Weigh-beam yand movable thereon, a movably mounted pawl for locking said poise against movement, means for holding said pa-Wl iu locking position, means for operating said pawl, and automatic means for holding said paWl in unlocking position.

4. In a Weighing device, in combination, a weigh-beam, a poise supported by said Weigh-beam and .movable thereon, a slidably mounted pawl for locking said poise against. movement, means iior normally holding said pawl in lockingl position.. vand automatic means for rendering said lirst mentioned means ineffective to move said pawl into locking position.

5. In a weighing device, in combination, a Weigh-beam, a poise supported by said weigh-beam and movable thereon, a bodilyv movable paivl tor locking said poise against movement, means for norn'ially holding said pawl in locking position. means for moving said pawl into unlocking position, and niieans rendered effective by operation of said mov ing means for holding` said pawl in unlocking` position.

G. In a weighing device. in combination a Weigh-beam; a poise supported by said Weigh-beam and movable thereon. a bodihv movable paivl for loc'iringl said poise against movement. .springs normally tensioned for holding said patri in locking position. a manually operable cam mechanism for n'iov ing said pawl to unlocking position. and means rendered effective b v operation oi said cam.. mechanism for holding' said pawl .in unlocking position in opposition to the tension or" said springs.

7. ln a Weighing device, in combination, a Weigh-beam having a toothed or serrated surface extending therealong, a poise supported by said weigh-beam and movable thereon, a pavvl having an elongated serrated tace, means :for moving said paivl ttor engaging said faces to each other to locl'i .said paivl in position, means for releasing said locking engagement, and automatic means depending upon operation of said releasing means 'for holding said pawl in released position.

8. ln a weighing device, in combination, a AWeigh-beam having a serrated surface ei:- tending tlierealong, a poise supportedV by said Weigh-beam and movable thereon, a pawl mounted tor bodily movement on said poise and having an elongated serrated surface, resilient means mounted on said poise it'or holding said pavvl with said surfaces in engagement with each other to lockV said paivl in position, cam mechanism i'or releasing said locking engagement, and automatic means depending upon operation ot said cam mechanism for holding said paivl in -eleased position.

In a Weighing device, in combination, a Weigh-beam, a poise supported by said weigh-beam and movable thereon, means for locking said poise against movement, means for operating said locking means, automatic means for holding said locking means in unlocking position, and printing mechanism operatively connected to said moving means and operable only when said locking means is in said looking position.

l0. ln a Weighing device, in combination, a Weigh-beam, a poise movably supported by said Weigh-beam, a locking paivl carried by said poise, cam mechanism for operating said pavvl, and locking means operatively connected to said cam mechanism for holding said pavvl in unlocking position.

ll. ln a Weighing device, in combination, a Weigh-beam, a poise movably supported by said Weigh-beam, a locking paivl carried by said poise, cam mechanism 'for supporting said pavvl and having a cam Atace operatively connected to said paWl, said cain tace being provided with a lobe ior locking said paivl in unlocking position.

l2. In a Weighing device, in conibination, a Weigh-beam, a poise movably sup-ported by said Weigh-beam, a locking paivl carried by said poise, a cam for operating said pawl having a cam face ivitli a Contact connection to said paivl, said cam face being provided With a projecting lobe, and means for stopping said cam when said lobe has passed beyond the line between the center ot rotation of said cam and its operating contact point.

18. In a Weighing device, in combination, a Weigh-beam, a poise movably supported by said beam, a slide mounted on said poise.l a locking paivl carried by said slide and normally biased for co-operation with said Weigh-beam for locking the poise in posii ,ai nase Vweigh-beam t'or locking the poise in position, a cam co-operating with said slide in contacting relationship tor moving said paivl to unlocking position in opposition to said bias, a lobe for said cam positioned so the nose thereof passes beyond the operative contact point of tlie cam when the paivl is moved to unlocking position, and a stop for holding the pawl in unlocking positionand permitting the poise to be freely moved along the weigh-beam to balancing position.

l5. In a Weighing device, in combination, a Weigh-beam, a poise movably supported by said weigh-beam, a locking paivl carried by said poise, spring mechanism tor normally holding said paivl in position to lock said poise, cam mechanism for operating said pavvl and automatically holding it in one position against the influence ot said spring mechanism to hold the paivl in unlocking position, and a second spring mechanism operatively connected to said cam and tensioiied to hold the saine in another posi tion.

16. ln a weighing device, in combination, a poise, a locking paivl tor said poise, resilient means for holding said paivl in locking position, cam means tor operating said paivl yagainst opposition ot' said resilient means, a spring operatively connected to said cani means and being' stressed to exert pressure on said cam means, and means 'tor relieving the stress on said spring when the cam is moved toward the position corresponding to the locking position of said paivl.

17. ln a Weighing device, in combination, a poise, a locking pavvl mounted on said poise, and a heart-shaped cam for operating said paivl and automatically holding said paivl in a predetermined position.

18, In a Weighing device, in combination, a poise, a locking paWl slidably mounted on said poise, resilient means normally urging said pavvl to looking position, and a heartshaped cam co-operating with said paivl for normally holding it in unlocking position.

19. In a Weighing device, in combination, a poise, a locking paivl mounted for bodily movement on said poise, a heart-shaped cam co-operating With said paivl for holding it Vin unlocking position, means for operating said cam, printing mechanisincontrolled by said operating means, resilient means for urging said pawl toward locking position,

and resilient means Connected to said @am for urging said means to normal position following a printing operation.

20. In Weighing device, in combination, a

poise, a locking paWl for said poise, operating ineclmnisni for said pnwl, resilient means normally urging said paWl to locking position, a spring connected to said operating means, and means for placing sald LUCY S. LONG, f C. B. RATHBUN. 

